> Just a question:
>
> I know things like laptops are using multiple cells in series
> in their battery packs.

As do radio control aircraft, particularly helicopters, which
use multiple cell Li-Po batteries.

> But after repeated use and several charge/discharge cycles, wouldn't
> one of the cells start to maybe charge/discharge faster than the
> others? Or have a slightly offset voltage for some reason? In this
> case, applying voltage back to the battery pack (cells in series),
> would charge the cells unequally, no? Or perhaps overcharge some
> cells while undercharging others?

Yes. Yes. Yes. And yes.

> Is this a real problem? And how would one go about solving it?

A balancing charger which charges each cell individually.  There
are also balancers (which just try to even out the cells).  The
requirement is that the battery pack must have a second multiple
wire connector which brings out a connection to each cell.  That
second wiring harness is what is used by the balancing charger.

The primary harness is the 2-wire one where the series voltage
of the pack is used to power the electric motor(s) of the air
vehicle (helicopter, aircraft, etc).

						Lee Jones
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